How to bleed and replace brake fluid on a 2009 Yamaha Grizzly 550 4X4

Shop parts for a 2009 Yamaha Grizzly 550 4X4 ATV.

This guide from MotoSport covers the tools, safety, model-specific notes, step-by-step procedure and troubleshooting for draining, replacing and bleeding the hydraulic brake system on a 2009 Yamaha Grizzly 550 4X4. Follow each step carefully and work cleanly to avoid contamination of the system.

What you need

  • DOT 4 brake fluid – Yamaha specification (use only fresh, sealed fluid)
  • Brake bleeding kit or clear hose and catch bottle
  • Turkey baster or fluid siphon
  • Wrenches for bleed nipples (usually 8 mm or 10 mm) and reservoir cap tool
  • Rags, gloves & safety glasses
  • Torque wrench for caliper/hose fasteners (recommended for reinstallation)
  • Jack or ramps and stands to safely lift the ATV (if needed)
  • Brake cleaner and a disposable container for used fluid

Model-specific notes for the 2009 Yamaha Grizzly 550 4X4

  • The Grizzly 550 uses a hydraulic disk brake system front and rear with a master cylinder reservoir typically located near the handlebars for front brakes and a separate reservoir or combined line for rear brakes depending on factory configuration. Confirm reservoir locations before starting.
  • Use DOT 4 brake fluid unless your owner’s manual specifies otherwise. Do not mix DOT 4 with DOT 5 silicone fluid.
  • The Grizzly can have a linked brake system on some trims — if your machine features linked brakes, bleed the linked circuit as a unit following the order below. If unlinked, treat front and rear separately.
  • Brake lines and fittings on this model are OEM steel/banjo fittings; inspect for corrosion or damage and replace any compromised components before bleeding.

Preparation

  • Work in a well-ventilated, clean area out of direct sunlight. Keep rags handy to wipe spills immediately; brake fluid damages paint and plastics.
  • Park the ATV on level ground, set parking brake, and disconnect the negative battery terminal if you’re going to operate electrical components while bleeding.
  • Remove wheels if necessary for access to calipers. Secure the ATV on stands if wheels are off.
  • Clean around the reservoir cap and bleed nipples to prevent dirt entry.

Drain the old fluid from the reservoir

  1. Open the reservoir cap and carefully remove the diaphragm/foam pad. Use a turkey baster or fluid siphon to remove as much old fluid as possible from the reservoir.
  2. Refill the reservoir with fresh DOT 4 to the fill line. Do not overfill.

Bleeding order (general for Grizzly 550)

Start with the caliper farthest from the master cylinder and work toward the nearest. Typical order:

  • Rear-right (if rear on same circuit)
  • Rear-left
  • Front-right
  • Front-left

If your Grizzly has a linked system, follow the manufacturer bleed order printed on the reservoir cap or in the service manual; if unsure, follow the farthest-to-nearest method above.

Manual (two-person) bleeding method

  1. Attach a clear hose to the bleed nipple on the caliper you’re starting with. Submerge the other end in a container partially filled with fresh brake fluid to prevent air re-entry.
  2. Have an assistant slowly depress the brake lever/pedal several times, then hold firm at the end of the stroke.
  3. Open the bleed nipple about a quarter turn until fluid and bubbles flow into the hose. Close the nipple before the assistant releases the lever/pedal. Repeat until no air bubbles are visible and the fluid runs clear.
  4. Top up the master cylinder reservoir after each caliper until full but not overfilled.
  5. Repeat for each caliper in the bleed order. Always close the bleed nipple before the lever is released to avoid sucking air back into the system.
  6. After all calipers are bled, pump the brake lever/pedal to build pressure and check for a firm feel. If it feels spongy, repeat bleeding focusing on the calipers with air or the farthest caliper again.

One-person (pressure or vacuum) bleeding

  • Use a pressurized reservoir cap or vacuum pump on each bleed nipple per tool instructions. Maintain reservoir fluid level while pressurizing to prevent air entry.
  • Follow the same bleed order and check for bubbles until clear fluid is delivered from each nipple.

Finishing up

  • Wipe any spilled fluid immediately and inspect brake lines, banjo bolts and fittings for leaks. Torque fittings to OEM specs if available; otherwise tighten snugly but avoid over-torquing.
  • Reinstall reservoir diaphragm and cap. Refit wheels and torque axle/wheel nuts to spec.
  • Lower the ATV, reconnect battery if disconnected, and perform multiple brake applications at low speed in a safe area to bed the system in and verify full braking performance.
  • Dispose of used brake fluid according to local hazardous-waste regulations.

Troubleshooting

  • Persistent spongy brake pedal after multiple bleeds usually indicates remaining air, a soft seal, or internal master-cylinder issue — consider replacing the master cylinder or caliper seals if bleeding fails.
  • If brake lever sinks slowly under pressure, check for internal leaks or reservoir-to-master leaks.
  • Contaminated fluid (dark, oily or dirty) requires a complete flush of all lines and components; replace any rubber parts that show swelling or degradation.

Maintenance interval & tips

  • Replace brake fluid every 1-2 years or sooner if you ride in wet or high-use conditions to avoid moisture buildup and corrosion.
  • Inspect brake pads, rotor condition and caliper slide pins when bleeding. Replace worn pads and service sticky pins to ensure even braking.
  • Keep a spare master cylinder cap diaphragm in your tool kit and always use sealed brake fluid containers to avoid moisture contamination.

MotoSport reminder – perform the job methodically, use the correct DOT 4 fluid, and replace any questionable hardware while the system is open. If you encounter internal master cylinder problems or persistent leaks, consult a professional mechanic or schedule service with a qualified shop that specializes in ATVs.

Related Shopping Categories

Shop Brake Fluid for a 2009 Yamaha Grizzly 550 4X4 ATV.

Shop Brake Bleeders for a 2009 Yamaha Grizzly 550 4X4 ATV.

Shop Brake Pads for a 2009 Yamaha Grizzly 550 4X4 ATV.

Shop Brake Lines for a 2009 Yamaha Grizzly 550 4X4 ATV.

Shop Brake Tools for a 2009 Yamaha Grizzly 550 4X4 ATV.

Disclaimer: This guide is provided for general informational purposes only and is not intended to replace your motorcycle's official owner's manual. Always refer to your manufacturer's documentation for model-specific instructions, torque specifications, safety procedures, and maintenance requirements. If you are unsure or inexperienced, consider seeking assistance from a qualified mechanic or technician.